bf27391da5
This patch adds support for the LZ4 decompression algorithm to libpayload. It's what all the cool kids are using for decompression these days and has many interesting advantages over LZMA (and everything else I know of): blazing fast decompression (20(!) times faster than LZMA, twice as fast as LZO on my Cortex-A72), no memory requirements on decompression, and possibly in-place decompression support. It pays for that with a lower compression ratio (about 50% larger compressed size than LZMA, 10% larger than LZO for an ARM64 Linux kernel binary), but the boot time math still works in its favor for our IO speeds. This patch only adds the raw decompression functions for use by external payloads, we can later try integrating them in CBFS. It copies the decompression code itself unmodified from the upstream LZ4 library at github.com/Cyan4973/lz4 which will hopefully make it easy to update. The frame format parsing is reimplemented since the upstream version looks unnecessarily complex and unreadable for our needs. BRANCH=smaug BUG=chrome-os-partner:32184 TEST=With other patches, booted ARM64 kernel that got compressed from 15M to 5.1M and decompresses in 44ms. Change-Id: I65bdc4b2b19bd51c7b7e17a4e4b79da301a2a014 Signed-off-by: Patrick Georgi <pgeorgi@chromium.org> Original-Commit-Id: f8a1fc996d5b0234d07f567fa8163d0f802d5144 Original-Change-Id: I15c0620da05561ade2552b15ffdf6bb3afd7eb26 Original-Signed-off-by: Julius Werner <jwerner@chromium.org> Original-Reviewed-on: https://chromium-review.googlesource.com/282743 Original-Reviewed-by: Stefan Reinauer <reinauer@google.com> Original-Reviewed-by: Aaron Durbin <adurbin@chromium.org> Reviewed-on: http://review.coreboot.org/10845 Tested-by: build bot (Jenkins) Reviewed-by: Stefan Reinauer <stefan.reinauer@coreboot.org> |
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.. | ||
arch | ||
bin | ||
configs | ||
crypto | ||
curses | ||
drivers | ||
gdb | ||
include | ||
libc | ||
libcbfs | ||
liblz4 | ||
liblzma | ||
libpci | ||
sample | ||
tests | ||
util/xcompile | ||
Doxyfile | ||
Kconfig | ||
LICENSES | ||
LICENSE_GPL | ||
Makefile | ||
Makefile.inc | ||
README |
README
------------------------------------------------------------------------------- libpayload README ------------------------------------------------------------------------------- libpayload is a minimal library to support standalone payloads that can be booted with firmware like coreboot. It handles the setup code, and provides common C library symbols such as malloc() and printf(). Note: This is _not_ a standard library for use with an operating system, rather it's only useful for coreboot payload development! See http://coreboot.org for details on coreboot. Installation ------------ $ git clone http://review.coreboot.org/p/coreboot.git $ cd coreboot/payloads/libpayload $ make menuconfig $ make $ sudo make install (optional, will install into /opt per default) As libpayload is for 32bit x86 systems only, you might have to install the 32bit libgcc version, otherwise your payloads will fail to compile. On Debian systems you'd do 'apt-get install gcc-multilib' for example. Usage ----- Here's an example of a very simple payload (hello.c) and how to build it: #include <libpayload.h> int main(void) { printf("Hello, world!\n"); return 0; } Building the payload using the 'lpgcc' compiler wrapper: $ lpgcc -o hello.elf hello.c Please see the sample/ directory for details. Website and Mailing List ------------------------ The main website is http://www.coreboot.org/Libpayload. For additional information, patches, and discussions, please join the coreboot mailing list at http://coreboot.org/Mailinglist, where most libpayload developers are subscribed. Copyright and License --------------------- See LICENSES.